1. Field of the Invention
The invention relates to an optical coupling device, particularly to a device for dividing a light signal and for selectively transmitting a light signal to different receiving devices.
2. Description of the Prior Art
In optical systems utilizing optical fibers there has existed a need for an efficient means of dividing a light signal so that it may be transmitted to more than one receiving element. For example, it may be necessary to split a light signal transmitted by an optical fiber so that it is received and transmitted by two other optical fibers. Furthermore, it may be desirable to have one fiber receive more light than does the other. Also, it may be important to the system to allow light to be transmitted between one fiber and another in one direction while preventing transmission of the light between the fibers in the opposite direction. Another desirable capability for an optical system may be the use of a detector to monitor a light signal without interfering with its transmission between an emitter and a receiver and without unduly attenuating the light so transmitted. The prior art has produced no means to efficiently accomplish these various functions.